1. Technical Field
The present invention relates to an optical detection device, an electronic apparatus, and an optical detection method.
2. Related Art
In electronic apparatuses such as a cellular phone, a personal computer, a car navigation device, a ticket-vending machine, and a banking terminal, recently, display devices provided with a position detecting function in which a touch panel is arranged on the front face of a display unit are used. According to such display devices, a user can input information by pointing an icon or the like on a display image while referring to the image displayed on the display unit. As position detecting types using such a touch panel, for example, a resistive type, an electrostatic capacitive type, and the like are known.
Meanwhile the display area of a projection-type display device (projector) or a display device used for digital signage is larger than that of the display device of a cellular phone or a personal computer. Accordingly, in such a display device, it is difficult to implement position detection using a touch panel of the resistive type or the electrostatic capacitive type.
As a general technique relating to a position detecting device for a projection-type display device, for example, a technique disclosed in JP-A-11-345085 is known.
However, in the above-described general technique, although a hovering process in which a pointer (cursor) is moved in accordance with the position of an object (target object) can be easily performed, it is difficult to switch between the hovering process and a command process (determination operation) in which a point is determined or the like.
In a character-input application, the command process corresponds to a process (drawing command) in which a character is drawn at a position on a screen that corresponds to a position traced by an object (target object), and the hovering process corresponds to a process in which only a cursor is moved to a position on the screen that corresponds to a drawing target position without drawing a character.
In a case where switching between the two processes cannot be appropriately performed, for example, the drawing command is constantly executed, and accordingly, characters are continuously written as one-stroke writing, whereby a space between characters, an inter-character gap, or the like cannot be represented. On the other hand, in a case where only the hovering process (a cursor moving process) is constantly performed, drawing of a character cannot be performed at all although a drawing target position can be perceived.
In addition, a method may be considered in which a space between characters is represented by using a state (no-input state) in which neither the command process nor the hovering process is performed, in other words, switching between the command process and the no-input state is performed. However, in such a case, the hovering process is not performed, and there is a problem in that any drawing target position cannot be recognized.
Furthermore, in an application (for example, a file manager or the like) in which an icon on the screen is selected and executed, the command process corresponds to an icon executing command, and the hovering process corresponds to an icon selecting process. In such a case, when switching between the hovering process and the command process cannot be appropriately performed, there is a problem in that an icon intended by a user cannot be appropriately selected or executed.